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Page:Popular Science Monthly Volume 90.djvu/956

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��Popular Science Monthly

��Twisting a Wire When Pliers Are Not Available

IF it becomes necessary to twist a wire around an object to serve as a ferrule, or to draw parts together tightly, and pliers cannot be used to get the desired

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� ��Twisting a loop tightly around an object, using a stick instead of pliers

twist, the method illustrated will be found satisfactory. It is only necessary to make a loose loop around the part for the band and to apply a stick. — A. S. Thomas.

��Making a Plumb- Bob Level of a Wood Angle

THIS simple form of a plumb-bob level is very efficient and is easily con- structed of material found on any building job. It consists of two pieces of wood fastened to a block to form approximately a right angle. A piece is fastened firmly across the two legs of the angle, and a staple, nail or screweye is put in at the

���A V-shaped frame of wood with a plumb-bob and line attached to be used as a carpenter's level

��point A. Fasten to this a string and plumb-bob. Place the frame on two sur- faces as shown in the drawing. Make a mark on the crosspiece at the point where the plumbline crosses. Reverse the frame so that the leg B rests on one support and C on the other and make a mark on

��the crosspiece where the line crosses. Measure off a point halfway between these two marks and make a permanent mark D. This mark will be crossed by the plumb- line when the frame rests on a perfectly level surface. — B. Francis Dashiell.

��Saving Scrap-Gum When Making Tire Repairs

IN repairing pneumatic tires save the scrap-gum. This can be returned to the factory for credit. The value of this material when returned depends largely upon the condition of the rubber. The gum should be kept separate and free from foreign material. When unrolling gum or fabrics for cutting, unroll them so that the holland is on top; then roll the hoUand back. Do not destroy the holland, as it may be used to cover tube-plates.

��Measuring Circumference with Typewriter Spacing

HAVING occasion to measure a cir- cumference that figured out to tenths of an inch, and not having a rule marked to these divisions, I tried the following means of overcoming the difficulty. Going to a typewriter, I made a row of periods, with each tenth one a comma to show full inches, thus: 1... 2 3

This gave me a rule marked in tenths, also one that could be bent around shaft- ing, collars, etc. As nearly all typewriters make ten spaces to the inch it is an easy matter to accomplish what seems to be a difficult job. — J. Claude Crews.

��A Durable Dead Black for the Inside of Cameras

THE dead black used by most camera manufacturers, the composition of which has long been considered to be a secret of the trade, is a mixture of lamp black and celluloid solution, the latter being far superior to shellac varnish for the purpose. The lamp black is stirred in and thoroughly incorporated with the liquid. There is no difficulty in making the celluloid solution. Old photographic films may be cleared of adhering gelatine, washed and dried, then shredded as fine as possible.

A solution is then made by dissolving acetate in amyl to the consistency of syrup and thinning down the acetone with it. — H. G. Gray.

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